In May 1861, the United States Army seized the Virginia home of Confederate General Robert E. Lee and his wife, Mary Lee. During the Civil War, the Lincoln Administration converted the estate into a refugee camp for runaway slaves and a military cemetery, a burial ground that is known today as Arlington National Cemetery. In December 1882, seventeen years after Lee surrendered at Appomattox, the United States Supreme Court ruled that the federal government had unlawfully seized the Arlington estate without paying just compensation to the Lee family. It further held that the doctrine of sovereign immunity did not bar the Lees from bringing suit to vindicate their legal title to the property. In the aftermath of the Supreme Court’s ruling, Congress reached a settlement agreement with the Lee family. Arlington National Cemetery has remained the lawful property of the United States ever since. The Supreme Court’s ruling in United States v. Lee made clear that the Constitution is not suspended in wartime. At all times, legal and constitutional limits govern the exercise of official power. This article tells the story of United States v. Lee and places the case in historical context.